Friday, December 01, 2017

Super eruption worry

I think I saw a headline about this somewhere earlier in the week, but here's the summary at Nature:
Civilization-threatening super-eruptions may happen about every 17,000 years — more frequently than previously thought.

Jonathan Rougier of the University of Bristol, UK, and his colleagues analysed a database of 1,379 large volcanic eruptions from the past 100,000 years. They found that, in some cases, the magnitude of a large eruption had been rounded down, making it seem smaller than it actually was. They also concluded that the database is missing some eruptions.

By accounting for more and bigger eruptions, the team calculated that the recurrence rate of super-eruptions, which spew at least 1,000 gigatonnes of ash and rock into the air, ranges between 5,200 and 48,000 years, with a best guess of 17,000 years. Earlier estimates had placed this between 45,000 and 714,000 years.

The most recent super-eruption occurred in Taupo, New Zealand, 25,600 years ago.

No comments: